Heretofore, in order to calibrate flowmeters to determine if the readout produced thereby was accurate, it was necessary to take many different readings, depending on the type of meter being calibrated and manually perform various mathematical functions such as multiplying, dividing, and taking the square root so as to obtain a reading to be compared with the reading of the flowmeter. While if these calculations were punched into a calculator accurately they would produce a reading that could be compared with the meter reading, it was subject to error and was time-consuming. This presented a problem when there were a large number of meters to be calibrated.
Devices have been produced to automatically compute the flow rate of gas, however, oftentimes they are quite complicated. For example, in U.S. Pat. No. 3,752,393, there is disclosed a digital flow preprogrammed calculator which repeatedly solves expressions for determining the gas flow through an orifice in a pipeline. The calculator performs its calculation using digital techniques.
In U.S. Pat. No. 3,699,810, there is disclosed a device for monitoring a fluid pressure system wherein temperatures are measured and signals addressed in accordance with a predetermined program.